The present invention relates to a tool with working surfaces which transmit torque by their application against a workpiece and are provided with particles of friction material consisting of metallic or mineral material.
Wrenches/screwdrivers, as well as screwdriver bits having working ends of different shape are known as tools for the transmitting of torque. Depending on their development, slotted screws, Phillips screws or hexagon socket screws can be driven. As a rule, only alloyed steels are used for the manufacture of the screwdriver blades in order to satisfy the prerequisite of sufficient transmission of torque. In order to obtain corrosion protection, the working ends can be blackened and preserved or else provided with a nickel-chrome coating in an electroplating bath. The permanence of such protective measures is frequently insufficient. Upon electroplating, there is even the danger of hydrogen embrittlement of the working end. Furthermore, the danger of the working end sliding out of the screw head or the like is considerable and is dependent on the surface structure.